The present invention relates to a shift-lever unit, in particular for a motor vehicle, for transmitting movements of a shift lever to cable lines, in particular for controlling a vehicle transmission.
In a vehicle, the tilting movements of a shift lever are typically transmitted via cable lines (so-called push-pull cable) or a linkage to the transmission of the vehicle in order to change the gears. In this case, the shift lever is usually mounted so as to be rotatable about two axes perpendicular to one another in order to permit an independent tilting movement in two planes perpendicular to one another.
In conventional shift-lever units, the cable lines or the linkage are/is often fastened directly to the respective axis of the shift-lever mounting, so that a rotation about the axis is converted into a rotation of the transmitting cable or the linkage, which in turn transmits the rotary movement to the transmission. In this case, however, the following difficulties arise:
Cable lines, which on account of their simple assembly and low weight have many advantages for use in a vehicle, are primarily suitable for the transmission of pulling movements. However, the precise transmission of rotary or torsional movements, as are necessary in shift-lever units according to the prior art for controlling the transmission, imposes very high demands on the rigidity and fatigue strength of the wire cable used. On the other hand, excessive rigidity impairs the flexibility during the displacement of the cable line in the vehicle.
Although a linkage avoids the abovementioned problems, it requires substantially greater outlay and thus considerably higher costs, since the individual components such as rods, joints or bearings have to be additionally fitted between the shift-lever unit and the transmission and have to be dismantled in the event of a repair.
The problem underlying the present invention is therefore to provide a simple and inexpensive-to-produce shift-lever unit which converts tilting movements of the shift lever into linear movements in order to be able to use sufficiently flexible cable lines for the precise control of the transmission.
The invention relates to a shift-lever unit for converting tilting movements of a shift lever into pulling movements of two cable lines, comprising a housing unit which defines two rotation axes perpendicular to one another, a frame unit which is mounted on the housing unit so as to be rotatable about the first rotation axis and to which the first of the two cable lines is fastened, a deflecting unit which is mounted in a rotatable manner on the housing unit parallel to the first rotation axis but so as to be offset from the latter and to which the second of the two cable lines is fastened, and a shift lever which is mounted in said frame unit so as to be rotatable about the second rotation axis and which is operatively connected to the deflecting unit in such a way that tilting of the shift lever about the first rotation axis essentially leads to a pulling movement on the first cable line, and tilting of the shift lever about the second rotation axis leads to a rotation of the deflecting unit and thus essentially to a pulling movement on the second cable line.
The shift lever preferably comprises a projection and the deflecting element preferably comprises an opening in which the projection engages in order to rotate the deflecting element. In this case, the opening is preferably of rectangular design, and the projection acts in the opening of the deflecting element on a slide, which is mounted in a slidable manner and can slide in a reciprocating manner in the opening for compensation during rotation of the deflecting element.
The first cable line is preferably fastened to a slide, mounted in a slidable manner, in a rectangular recess of the frame unit, the slide being able to slide up and down during the tilting of the shift lever about the first axis for compensating for the up and down movement of the recess.
The second cable line is also preferably fastened to a slide, mounted in a slidable manner, in a rectangular recess of the deflecting element, the slide being able to slide up and down for compensating for the up and down movement of the recess.